Thyroid carcinoma in children and adolescents in Ukraine after the Chernobyl nuclear accident - Statistical data and clinicomorphologic characteristics

BACKGROUND. The increase in the number of childhood thyroid carcinoma cases in Ukraine after the Chernobyl nuclear accident in 1986 prompted the devel opment of a registry of thyroid carcinoma cases at the Institute of Endocri nology and Metabolism in Kiev. In the current study, the authors report the statistical data and clinicomorphologic features of the cases included in this registry. METHODS, To study the incidence, and age and gender distribution of thyroid carcinoma in Ukraine, the authors compiled complete clinical information f rom cases diagnosed and treated at the Institute of Endocrinology and Metab olism and statistical reports submitted to the registry from 27 regions of Ukraine. Morphologic features of the resected tumors were examined and were included in the database. RESULTS. During the 5 years preceding the Chernobyl nuclear accident, a tot al of 59 cases of thyroid carcinoma were identified in the birth to 18 year s age group (25 in children age less than or equal to 14 years and 34 in ad olescents ages 15-18 years). Between 1986 and 1997, the total number of thy roid carcinomas in Ukrainian children and adolescents was 577 (358 children and 219 adolescents). Morphologically, the thyroid tumors overwhelmingly w ere papillary carcinomas, and the majority of these also showed a follicula r and/or solid growth pattern. Lymph node metastases and other extrathyroid al spread were common, thus necessitating total thyroidectomy and lymph nod e dissections in many patients. CONCLUSIONS, Between 1990 and 1997, a significant increase in the incidence of thyroid carcinoma was noted in children and adolescents in Ukraine; the group most affected was comprised of the individuals who were age less tha n or equal to 5 years in 1986 (the year of the Chernobyl nuclear accident). The largest number of cases occurred in patients living in areas of thyroi d radiation doses of greater than or equal to 0.50 grays. The morphologic f eatures of those thyroid tumors suggest that they are aggressive tumors wit h a high frequency of lymph node metastases, venous invasion, and extrathyr oidal spread. Cancer 1999;86:149-56, (C) 1999 American Cancer Society.